Highlights of Equus Beds Ground-Water
Recharge Project

Gallons of Water Recharged Through May 2002^*
(data from the city of Wichita)

Year	Halstead	Sedgwick¹	Total
1997	130,622,100	1,828,900	132,451,000
1998	258,947,500	40,360,300	299,307,800
1999	243,059,200	82,285,300	325,344,500
2000	86,436,400	11,530,700	97,967,100
2001	211,182,000	---	211,182,000
2002 ____	16,917,400 ___________	--- ___________	16,917,400 ___________
Sum	947,164,600	136,005,200	1,083,169,800

¹Sedgwick total volume does not include the 29,842,800 gallons
recharged through the earthen presedimentation basin.

^*Artificial recharge activities at these sites ceased after May 2002 with the
conclusion of the demonstration phase of the Equus Beds Ground-Water
Demonstration Project.

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Ground-Water Quantity in the Equus Beds Aquifer

Water-level declines of as much as 40 feet reached a maximum in most wells from September 1940, before pumping began, to lows occurring in October 1992 at the climax of the 1988-92 drought as a result of increased city and agricultural pumpage and drought conditions.

Between October 1992 and January 2006, water levels recovered by more than 10 feet in much of the study area. This is primarily a result of reduced city pumpage caused by an increasing reliance by Wichita on Cheney Reservoir as a water-supply source and normal to wetter-than-normal climatic conditions. Irrigation pumpage increased during most of this period. Aquifer-storage volume recovered about 55 percent during the same period. Water levels in many wells recovered to levels similar to those in the late 1970s to early 1980s.

Artificial recharge to the Equus Beds aquifer during the Equus Beds Ground-Water Recharge Demonstration Project (1997-2002) was equivalent to less than 3 percent of the water pumped for municipal use from the aquifer by the city of Wichita. Wichita plans to resume artificial recharge of the Equus Beds aquifer during periods when flows in the Little Arkansas River are greater than the minimum streamflow discussed in the following section “Surface Water Quantity” and after completion of construction of Phase I of the Equus Beds Aquifer Storage and Recovery Project (scheduled for completion in September 2006).

Click here for more information about Changes in Ground-Water Levels and Storage in the Equus Beds Aquifer northwest of Wichita, Kansas.

Real-Time Ground-Water-level links for the Equus Beds Aquifer

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Surface-Water Quantity

The source water for the Equus artificial recharge project is the Little Arkansas River. During the demonstration phase of the project, according to permit conditions set by the Kansas Department of Agriculture, Division of Water Resources, water for recharge could be diverted from the stream for recharge at the Halstead recharge site when streamflow at the USGS stream gage Little Arkansas River at Highway 50 near Halstead (07143672) was greater than 42 ft3/s from April 1 through September 30 and 20 ft3/s from October through March 31. Water could be diverted for recharge at the Sedgwick recharge site when streamflow was greater than 40 ft3/s at the USGS stream gage Little Arkansas River near Sedgwick, KS (07144100) throughout the entire year. Permit guidelines for full scale recharge operations established by the Kansas Department of Agriculture, Division of Water Resources, in August 2005, requires streamflow at the Little Arkansas River at Highway 50 near Halstead stream gage to be greater than 57 ft3/s from April 1 through September 30 and 20 ft3/s from October through March. There are currently (March 2006) no permit regulations established for full scale recharge operations based on streamflow at the Little Arkansas River near Sedgwick stream gage.
The number of days per year when streamflow exceeded minimum diversion requirements is tabulated below. Demonstration permit requirements are used from 1995 through 2004 and full scale operation requirements are used for 2005 for the Little Arkansas River at Highway 50 near Halstead. Demonstration permit requirements are used for all years for the Little Arkansas River near Sedgwick site.

	Number of days per year exceeding minimum flow requirements for stream diversion according to state permits

	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005
Little Arkansas River at Highway 50 near Halstead, KS (07143672)	114	130	270	199	349	228	168	99	151	151	144*
Little Arkansas River near Sedgwick, KS (07144100)	210	180	318	301	365	290	226	143	218	258	239
	*Number of days per year exceeding minimum streamflow calculated using 2005 permit requirements.

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Water Quality

Since 1995, water-quality samples have been collected from 10 surface-water sites and more than 100 ground-water sites as a part of the Equus Beds Ground-Water Recharge Project. More than 5,100 water-quality samples have been collected and analyzed for more than 400 compounds, including most of the compounds on the U.S. Environmental Protection Agency’s Maximum Contaminant Level (MCL) List for drinking water, since 1995. The station name and number for water-quality monitoring sites are listed in the following link— Equus Beds Ground-Water Recharge Project water-quality monitoring sites.
The report “Baseline Water Quality and Preliminary Effects of Artificial Recharge on Ground Water, South-Central Kansas, 1995-98” and fact sheet “Effects of Artificial Recharge on Water Quality in the Equus Beds Aquifer, South-Central Kansas, 1995-2000”, identify sodium, chloride, total coliform bacteria and atrazine in surface water and nitrite plus nitrate, arsenic, iron and manganese in ground water as constituents to monitor because they frequently (at least 20% of samples collected during baseline sampling) exceeded their respective water-quality standards and criteria in some surface and ground-water samples. The following link is a summary table of selected data that exceeded their respective water-quality criteria in surface-water samples collected from February 1995 through December 2005. Data summary for surface-water monitoring sites. The summary includes the water-quality criteria, number of samples collected, percentage of detected compounds, percentage of samples exceeding the water-quality criteria as well as the median for each compound.
Ground-water quality was monitored at 30 wells throughout the study area before recharge activities began to establish a baseline comparison for monitoring the effects of artificial recharge on the Equus Beds aquifer. After 6 years of artificial recharge activities, constituents that were identified as needing monitoring in the ground-water remained the same as those identified before artificial recharge activities began. Average concentrations of selected data before and after artificial recharge activities are presented in the following link — Data summary for effects of artificial recharge.
Data collection from the Areal Index Assessment Network began in November 2001 with the objective to define general water quality and quantity and to monitor changes of both in the Equus Beds aquifer. This network of 76 monitoring wells is completed in the 150-square-mile area located north of the city of Wichita ( study area map). There are 38 locations every 4 square miles with a deep and a shallow monitoring well completed at each location. The following link provides a summary of selected data in samples collected from November 2001 through December 2005. Data summary for Areal Index Assessment Network.
Data collection from 10 Aquifer-Storage and Recovery (ASR) prototype wells began in December 2002. Data collection from 2 additional ASR prototype wells began in June 2004. Data from these wells will be used in conjunction with data collected during the demonstration phase of the project (1995-2000) along with data that continues to be collected from surface-and ground-water sites to determine the effects of artificial recharge on water quality. The following link provides a summary of selected data in samples collected from December 2002 through December 2005. Data summary for ASR prototype wells.
Concentrations and load estimates for the parts of the Little Arkansas River indicate that the sources of the loads of chloride and fecal coliform bacteria are upstream of Highway 50 and that atrazine loads are distributed throughout the basin. For further information refer to “Regression Analysis and Real-Time Water-Quality Monitoring to Estimate Constituent Concentrations, Loads, and Yields in the Little Arkansas River, South-Central Kansas, 1995-99.” Additionally hourly estimates of concentrations and loads from 1999 through today for these sites are available at http://ks.water.usgs.gov/Kansas/rtqw/
Click on the following links for complete statistical information on all sites sampled from February 1995- December 2005 as part of the Equus Beds Ground-Water Recharge Project:

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Highlights of Equus Beds Ground-Water Recharge Project

Gallons of Water Recharged Through May 2002* (data from the city of Wichita)

Ground-Water Quantity in the Equus Beds Aquifer

Real-Time Ground-Water-level links for the Equus Beds Aquifer

Surface-Water Quantity

Water Quality

Highlights of Equus Beds Ground-Water
Recharge Project

Gallons of Water Recharged Through May 2002^*
(data from the city of Wichita)